Stop West Nile Spraying Now

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Oppose Ineffective and Unsafe Adulticiding


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    Our opposition to spraying pesticides from the air over populated areas to kill adult mosquitoes (adulticiding) rests on two very simple facts: 1) it does not work, and 2) it is dangerous to some people in the short term and adds to the overall pesticide load in the environment for the long term. The second point is moot given that adulticiding is ineffective, but it is important because spraying continues as West Nile virus recedes into a state known as chronic endemicity, one in which very few people are infected. Moreover, indiscriminate spraying can increase resistance in non-target insects so that there might be no effective control available when an actual threat appears, and it harms beneficial insects, whose recovery cycle is often much longer.  The question is not whether to spray; rather, it is if we should use effective means of control instead of ineffective and damaging ones. 

    Public officials have exaggerated the threat of WNv in an attempt to justify their spray protocol. Their statements and reasoning have shifted regularly since WNv became a concern in this region in 2005, always suggesting that we must use indiscriminate aerial spraying. However, a sensible public policy would eschew aerial adulticiding and emphasize instead careful water management and the targeting of mosquito larvae (larvaciding), as some other cities do. Examples are our nation's capitol Washington, D.C., Nashville, Tennessee, and Fort Worth, Texas.

    As to efficacy, the Sacramento-Yolo Mosquito & Vector Control District (SYMVCD) has supplied no evidence that spraying adulticides is effective in slowing the transmission of WNv to humans. In fact, scientific research and mathematical modeling demonstrate that spraying is ineffective because mosquito populations quickly rebound to their prior levels. Even with this lack of efficacy the District refuses to resurrect its program of development of safe and effective biological controls.

    In spite of the scientific evidence to the contrary, public officials promote a 2008 paper about the 2005 spraying of Sacramento as evidence of efficacy, but because their work involves serious methodological and scientific problems no conclusions at all can be drawn from it. Rigorous review by independent scientists was avoided – in response to our Public Record Act requests the authors were able to produce no reviews of their paper whatsoever (item #5).

    Vector control and public health officials declare an epidemic when a certain threshold is reached, which involves infected mosquito pools, dead birds, and horses but no longer includes human cases. "Epidemic" seems to be an exaggerated word up front, particularly as many people view the term and with human infections removed from the spray trigger. They then insist that they must spray to "break the transmission cycle," an impossibility with this spray program.

    The National Centers for Disease Control (CDC) indicates that 80% of people infected with WNv will not develop any illness or symptoms, 20% will have mild flu-like symptoms, and 1 in 150 have serious symptoms. In 2011 there were 9 deaths of people in California infected with WNv (California Department of Public Health data). While any death is tragic, and while we strongly support effective preventive measures, comparing the 9 deaths in California in 2011 of people infected with WNv to the 7000 or more flu and pneumonia-related annual deaths reveals the extent of the official exaggeration. The spraying supposedly justified by an "epidemic" is then a badly out-of-proportion public health response to a relatively small threat. We always need to spend our public funds where they have the greatest positive effect, but this seems particularly true in these difficult economic times. 

"Indiscriminate spraying of pesticides, especially in heavily populated urban areas, is far more dangerous to human health and the natural environment than a relatively small risk of West Nile Virus." -- Concerned Physicians and Scientists
"Can anyone believe it is possible to lay down such a barrage of poisons on the surface of the earth without making it unfit for all life?" -- Rachel Carson
Sign up for Spray Notification.
Form to make a claim for damages from spraying.

Cities, counties nationwide begin mass aerial sprayings of toxic 'anti-West Nile Virus' pesticides.

Mosquito Aerial Spray Programs Endanger Human Health, Don’t Work.

Refuting the Myth – No Such Thing as a Safe Dose.

First, Do No Harm.
SYMVCD: Not to Worry – We Just Waste Taxpayer Money.
New Study: Sacramento Area Is Delta's Top Pesticide Source.
"Safe" Pesticides Now First in Poisonings.
        Entomologist Calls ULV Spraying Ineffective and Risky.
CDFA Calls Off LBAM Spraying in Populated Areas.
   SYMVCD Sprays in Spite of Zero Human Infections.  

Inefficacy Halts Nashville Spray Program.
2005 Sacramento Spray Report Is Fatally Flawed.

Fort Worth Says "No" to Adulticiding.
Washington, D.C., Says "No" to Adulticiding.
SYMVCD Fails to Implement Safe and Effective Biological-Control Methods.
"There is no credible evidence that spraying pesticides used to kill adult mosquitoes, also known as adulticides, reduce or prevent WNV incidents or illnesses." -- AIMM Platform

Children playing

"The most alarming of all man’s assaults upon the environment is the contamination of air, earth, rivers, and sea . . . " -- Rachel Carson

Murphy's Law of Pest Control.

From a website about natural pest control: "To treat a malaria outbreak in Borneo in the 1950s, the World Health Organization (WHO) decided to spray DDT to kill mosquitoes.  The DDT also killed parasitic wasps which were controlling thatch-eating caterpillars.  As a result, the thatched roofs of many homes fell down, and the DDT-poisoned insects were eaten by geckoes, which were in turn eaten by cats.  The cats perished, which led to the multiplication of rats, and then outbreaks of sylvatic plague and typhus.  To put an end to this destructive chain of events, WHO had to parachute 145,000 live cats into the area to control the rats."  Hopefully pyrethrins, pyrethroids, PBO, and the "inert" components will not raise such havoc, but a lot is unknown about these chemicals and there are often unintended effects, as the Weston study has already demonstrated.

Study fails to demonstrate that spraying is effective.
A study out of the Harvard School of Public Health in August of 2006 showed that spraying was ineffective in preventing the spread of West Nile virus.

How effective is spraying adulticides?

"Treating mosquitoes with spray is . . . analogous to trying to machinegun mosquitoes in flight as opposed to attacking their life support while they are relatively fixed in the water. The former is mathematically difficult to impossible and dangerous. The latter, while requiring more thinking, is less dangerous and very effective (as shown by data) . . .  "

Martin Walter, Professor of Mathematics, University of Colorado, Boulder.      See full text.

The dose is so low that there can't possibly be any harm!  Or can there?
Apparently the argument by vector-control and public-health officials is that even though there is no credible evidence that spraying works, we might as well give it a try since the dose is so low --  just maybe it will work.  At best this would be a waste of money and time, but officials are ignoring substantial evidence of risk even at low doses . . .
  See full text.

Since Silent Spring -- got politics?
In his book, Since Silent Spring, Frank Graham, Jr., noted that "Rachel Carson has been proved right" and posed the question "What have we done about it?"  Peruse these passages and notice some striking similarities with what is going on today relative to West Nile virus.

Faith-based vector control?
A recent letter to the editor, suggesting that without any scientific evidence to show that adulticiding slows the transmission of WNv to humans, using it as part of a control strategy amounts at best to a matter of faith on the part of SYMVCD.

Propaganda from SYMVCD and CDC?

District Manager David Brown made this presentation at a CDC conference.  In spite of errors, misrepresentations and false claims the director of the CDC has refused to remove it from the website.

Presentation to Sacramento City Council 8/9/07.

Download a PowerPoint presentation made to the Sacramento City Council on August 9, 2007, by a group of Sacramento residents, who asked the Council to pass a resolution requesting an opt-out of the aerial spraying.

All roads lead to spraying?
Local officials have long said that the reason to spray urban areas aerially is that we cannot get at back yards, where Culex pipiens hide, any other way.   Now that we point out that Washington, D.C. officials control Culex pipiens without spray, our officials suddenly give Culex tarsalis, a rural mosquito, as the new reason to spray urban areas.  What is wrong with this picture?

Are there good alternatives to spraying adulticides?

A number of locales around the country (e.g. Cheyenne, Boulder, Ft. Worth, and Washington, D.C.) have elected not to spray and have achieved equal or better results than surrounding locales that have sprayed.    See full text.

Have WNv risks been exaggerated and spraying risks largely ignored? 

As communities around the country have dealt with this issue, some strong statements have been made that suggest that the media and local public-health officials have exaggerated the WNv risk while ignoring very real risks from spraying of adulticides and the ineffectiveness at stopping the transmission of WNv to humans.  We list a few of them here.

Do these pesticides pose any risks?

The U.S. EPA classifies PBO as a Group C-possible carcinogen.  Poisonings by the so-called "safe" pesticides are on the rise, and these chemicals are harmful to some people in the short run and pose threats to all of us in the long run by increasing the mutagens in the environment  . . .     See full text.

Our responses to questions vector control officials did not answer.

The District was presented with many citizens' questions from public forums, one held by Stop West Nile Spraying Now on 8/22/05 and one officials walked out of in the City chambers on 8/23/05 (see City Forum).  The District failed to answer many questions and gave partial, misleading, and factually incorrect answers to others . . .   See full text

Does this protect the public health or is it a grand hoax?

An op-ed for the Davis Enterprise on August 13, 2006, suggesting that the decision to spray Davis was a political one that had nothing to do with the public health.

"Inefficacy and Risks of Adulticiding for West Nile Virus"  

A presentation by Susan JunFish, of Parents for a Safer Environment, in Contra Costa County.

Citizens' open house at SYMVCD, 6/23/07.

A group of local residents attended the open house and voiced their concerns about the spraying.  Here is the press release.

No Spray Sacramento position paper on spraying.

A position paper discussing how mild the disease is, the known and unknown risks from the spray, and how spraying is risky and might make matters worse.

Is Trochet Using Chemical Industry Propaganda to Misinform?

Some statements of Dr. Glennah Trochet, public health officer for Sacramento County until mid-September of 2011, seemed to be more from a spokesperson for the chemical and pesticide industries than as an official whose primary responsibility is the health and welfare of the public.

Background textures by GRsites.